Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
20 Cards in this Set
- Front
- Back
|
Cycles are illustrated by an up-and-down wave called a(n) |
oscillating signal |
|
|
The distance between peaks of an electromagnetic wave is called the |
wavelength |
|
|
A million cycles per second is a(n) |
MHz |
|
|
A weakening electromagnetic signal does not impact which two characteristics |
wavelength and frequency |
|
|
Two signals that have the same peaks and valleys are called |
in phase |
|
|
What are categories of the electromagnetic spectrum |
1.) X-ray 2.) microwave 3.) radio |
|
|
The number of inlicenced bands that are used for WLANS is |
2 |
|
|
What are the names of electromagnetic signal that has been modified to carry information |
1.) carrier signal 2.) carrier wave 3.) carrier |
|
|
The modification of the height of a digital signal is called |
amplitude shift keying |
|
|
A________is a basic unit of power of 1 amp of currect flows at 1 volt |
W(watt) |
|
|
The power that most WLANs tranmit is less then |
200mw |
|
|
The refence point that relates the logarithmic relative decibel (dB) scale to the linear milliwatt scale is known as the |
decible milliwatt (dBm) |
|
|
a lost of 3 decibels means that______percent of the power in mW has been lost |
50 |
|
|
What is the recommend signal strength for WLAN |
-70 dBm |
|
|
Why should RSSI should not be used as a true indicator indicator of signal strength |
RSSI is not a linear scale |
|
|
The materials concrete, wood, and asphalt that "soak up" an rf signal can all cause |
absorption |
|
|
What is the differnce between refraction and differaction |
With refraction, the medium through which the signal passes causes the signal to bend, while diffraction is caused by an object in the path of the transmission |
|
|
Free space path loss (FSPL) is caused by |
the loss of signal strength as the signal travels |
|
|
A(n) ______is one billionth of a second |
nanosecond |
|
|
_________occurs when multipath signal arrives 180 degrees out of phase |
nulling |
